When the financial crisis arrived on the shores of Dubai and the workforce constructing the seemingly endless line of exotic hotels and private golf courses was told to down tools, it was a bigger blow to the villages of Pakistan and Bangladesh than the tiny emirate's treasury coffers. Almost all of Dubai's 2 million population comprises foreign nationals who send home 40% of everything they earn, according to the World Bank.

Bangladeshis, Pakistanis and the Chinese are among the most numerous nationalities in Dubai. There are also several thousand Britons.

Buried in the data on global remittances is a surprising fact: some developed countries are now net importers of cash, as professional people working abroad send increasing amounts of cash home. According to the World Bank, France benefited from a huge remittance inflow of $18.9bn in 2011, more than the $14.8bn that left the country.

Bank of England figures would also make Britain a net winner, with $8bn coming in and $3.2bn sent overseas. However, the World Bank says this figure is a huge underestimate and the real outflow figure is closer to $20bn.

The biggest loser in the remittance game isn't hard to guess. More than $100bn leaves the US every year, bound for destinations as varied as Tonga, Ukraine, Costa Rica and, yes, China. Around $6bn flows back in, according to 2010 figures. Such capital flight would be enough to capsize all but the largest economies.